How do you handle inline classes? On 1.4.x we've e...

# multiplatform

[Paul Woitaschek]

How do you handle inline classes? On 1.4.x we've exposed the kotlin duration to ios. But now with the changes of the internal representation from millis to long the exposed value isn't usable any longer.

I thought about `actual typealias`ing it for ios to a regular class and keep duration for android but that won't work either because you'd need to chose between an interface and a class.

[louiscad]

How is it no longer usable?

[Paul Woitaschek]

Well in objective c, inline classes just get exported as the value they wrap

[louiscad]

Just like in Java

[Paul Woitaschek]

So in 1.4.32 having a duration in public api means exposing nanoseconds:
https://github.com/JetBrains/kotlin/blob/9e50a239b4f34406a6c6f987b29d5ceedca777a8/libraries/stdlib/src/kotlin/time/Duration.kt#L12

[louiscad]

Is it actually always in nanoseconds?

[Paul Woitaschek]

Yes it is

[Paul Woitaschek]

But now with 1.5 it was changed to long

[Paul Woitaschek]

And based on some bitmagic it either uses nanos or millis:
https://github.com/JetBrains/kotlin/blob/e73e039e43d740b890eaa4d7256362eeaf6ff1f7/libraries/stdlib/src/kotlin/time/Duration.kt#L38

[Paul Woitaschek]

So now having kotlin duration in your public api is unusable from obj-c

[louiscad]

Well, you can add overloads for Obj-C, or if the type is not an interface, extensions will also work and be seen like members in Swift/Obj-C.

[louiscad]

(If it's an interface, you might want to make it a stateless abstract class instead)

[Niek]

> So now having kotlin duration in your public api is unusable from obj-c
I guess this is still an issue? We're just getting Int64 on the iOS side which, depending on internals, is either millis or nanos with an extra unit discriminator in it